Lighting control apparatus for airdromes



Aug. 2 5, 1936,

G. H. WILLIAMS LIGHTING CONTROL APPARATUS FQR AIRDROMES 3 Sheets-Sheet 2 Filed- Oct. 3, i929 ATTORNEYS Patented Aug. 25, 193$ LIGHTING con'rnoit ArPAne'rUs FOR AIRDROMES Gui-don H. Williams, Birmingham, Ala. Application October 3, 1929, Serial No. 397,134

9 Claims.

My invention relates/to apparatus for indicating conditionsaifecting aerial navigation at air.- dromes, and has for its object the provision of apparatus which shall be operable from a remote point by aradiant energy signal.

A further object of my invention is to provide apparatus for indicating conditions affecting.

puslights and groups of lights for indicating wind direction and safe direction of approach for airplanes and in which the indications of'said lights are automatically controlled by winddirection modified by wind speed.

A particular objectof my invention vide means whereby the lights for indicating wind direction and for illuminating a landing field may be selectively and automatically controlled and may be put into operation by an aviator before landing through the medium of aradiant energy signal." With such an arrangement, it will be apparent that the necessity of maintaininglights and operators therefor at an airdrome lights areselectively and automatically controlled by means responsive to wind direction, such as a wind vane, and means responsive to wind velocity, such as an anemometer. The circuits controlling the flood lights are operated from a master control circuit which, when closed, permits the automatic operation above referred to.

The master control'circuit is operable by means responsive to a radiant energy signal from a re- I mote .point and means are included whereby'such,

5 a signal must be of apredetermined sustained is to pro-'- through all' hours of the night is obviated and, that the expense of a continuously lighted system duration, thereby obviating possible closing of the master control circuit by stray radiant eny signals. Furthermore, there is included in the master control circuit a relay which operates after the circuit is once closed to hold it closed until it is opened manually, thereby insuring that the lights will remain on until a landing has been made.

Apparatus embodying features of my invention .is shown in the accompanying drawings, forming a part of this application wherein Figure 1 is a diagrammatic drawing of the circuits and lighting arrangements together with their controlling means.

Fig. 2 is a diagrammatic view showing circuits which may belenergized with wind in direction indicated and only one flood light lit; and.

Fig. 3 is a diagrammatic view showing circuits which may be energized when no wind is blowing and with bothflood lights lit. c

Referring to the drawings for a better understanding of my invention, I show a pair of flood lights ill and ii for lighting a landingfield, though any suitable numbermay be employed. As is well understood in the art to which my invention relates, airports are generally provided with a plurality of such flood lights, arranged around the landing field, which are lighted singly,

or at times more than one flood light is lighted,

to. afford general illumination of the fleld when an airplane is landing or takingoff. In all cases,

they are lit so as to aflord such illumination without causing a glare in the eyes of the aviator. In appropriate position on or near the field are located. a plurality of wind direction indicating lights, in this instance nine being shown and numbered from I! to 29 inclusive. -It] will be noted that the wind direction indicating lights are arranged in squares whereby thewusual T- outline of lights may be made for indicating wind direction. with the number of lights shown, four different directions of the wind at to each other may be indicated though itwill be obvious that by increasing the number of lights and'providing appropriate circuits as hereinafter explained, the number of indications may be increased accordingly. a

.The control, both of the flood lights J0 and I] and of the wind direction indicating lights 12 to "inclusive, is automatically maintained through aplurality-ofsecondary circuits which will bebeing understood that when thefmaster control voltage current throughthe circuit and from. thence back to the conductor 6|. The heating through a transformer 26, to the grid circuit 8'! 01 a vacuum tube 28. The plate circuit is shown at 29 and includes therein a relay 3| controlling an armature 3|a. The grid circuit 81 is normally so biased by a battery 82 that the current in the plate circuit 28 is too low to operatethe relay 3|. When an incoming radiant energy signalpasses through the receiver 28, it affects the grid bias so as to increase the current in the plate circuit 28 and energizes the relay 8| to move the armature (Ha.

When the relay 3| is energized, a circuit is made from a battery 66 through a conductor 31, a conductor 38, armature 3|a, and conductor 88 to a relay 4| which controls armatures Ma and MD. The circuit continues through the relay 4|, energizing it, thence through a conductor "to a bimetallic temperature responsive member 46 movable between contacts 46a and 46b. In the posi- I tlon shown, the bi-metallic member is in contact with the contact 46a so that the circuit being described continues through the bi-metallic member 46 to a conductor 41 and from thence to a conductor 48 and a conductor 48 back to the battery 86.

At 6| and 62 are shown conductors which are connected to a suitable source of relatively high voltage such as volt, 60 cycle current. with the relay 4| energized a high voltage circuit is made through conductor 62', armature 4|b, and from thence through a conductor to a heating element 54 which is disposed adjacent the bimetallic member 46. From the'heatingelement 64 the circuit continues through a conductor 68 to a rheostat 51 which controls the flow of high element 54 raises the temperature of the bimetallic member 46 causing it to move toward the contact 46b. As soon as the bi-metallic member 46 leaves the contact 46a, a holding circuit is established through the relay 4| i'rom conductor 31, through conductor 88, armature 8|a,- conductor 38, relay 4|, armature Ma and conductor: 48 and 48 back to battery 88. a

As soon as the bi-metallic member 48 has been heated sumciently to move into contact with the contact 46b, a circuit is completed from battery 86 through conductor 31, and conductor 48 to a push button 6 I, the latter being of the type which is normally closed but which may be held-open manually. From the push button 8| the circuit continues through a conductor 82 to a master relay 68 which controls armatures 68a and 88b. From the relay 68 the circuit continues through a conductor 64 to the contact 48b and. thence through bi-metalllc member 48, conductors 41,

master relay 63 is energized and holds the master control circuit closed through the armature 63a and once it is closed, it can not be reopened until the push button 6| is manually operated.

In order. that the master relay 63 may be energized, and the master control circuit closed, when desired, without operation of the radio receiving set 25, I provide conductors 10 and H connected respectively to the conductors 48 and 64 and which may be connected by means of a manually operable switch 12.

Itwill be noted that in order to complete the master control circuit in response to a radiant energy signal through the receiving set 2.5, it is necessary that the signal be continued or sustained for a sufiicient duration for the relays 3| and 4| to remain energized a sufficient length of time for the heating element 54 to raise the temperature of the iii-metallic member 46 sufiiciently to cause it to move into contact with the contact 4612. The time required for this movement to take place may be adjustably controlled by means of the rheostat 51. I

It will be seen therefore that my improved apparatus is not operable in response to stray rabring about energization'of the relays 3| and 4|,

and cause the bl-metallic meinber 46 to start its movement toward the contact 46b, and not move sufiiciently to come in contact with the contact 48b, the relays 3| and 4| can not again become energized until the bi-metallic member 46 has cooled off suillciently for it to again come in contact with the contact 4611. It will thus be seen that my improved apparatus is well guarded against any operation other than an intendedand is connected to a conductor 84 leading to the plus side of battery 36 through conductor 3l.

The conductor 8| leads to a relay 86 and the conductor 82 leads to a relay 81, both of which relays are oi the "slow to release type. The relay 88 controls armatures 86a, 86b, 86c and 86d while the relay 8! controls armatures 81a, 81b, 81c and 81d. Connected to the other side of the relay 86 is a conductor 88 which is connected through condoctor 48 to the conductor 48 from the minus side of the battery 86. The relay 81 connects to the battery 86 through a conductor 88 connected to the conductor 88.

With the commutator 11 of the anemometer II in the position shown, the relay 86 is energized from the battery 36 through conductors 81 and 84 through brush 83 and anemomcter shaft to the commutator 11. From thence it con tinues through brush l8, conductor 8|, relay 86, conductor 88 and back to battery 36 through conductors 48 and 48. When a segment of the commutator 'Il moves into. contact with the brush 18, the relay 8! is energized through conductors 31 and 84. brush 18, conductor- 82, relay'81, con-' 2,052,383 ductor Bil, back to the conductor *etand con-- energized, closing the contacts mile and illflcl, a

ductors iii and to to the battery. It will thus be seen, that with a wind blowing and the anemometer rotating, the relays Bo and 81 are alternately energized. These relays being of the slow to re lease type. with a wind of a predetermined minimum velocity, both relays remain energized. It the velocity of the wind falls below such a minimum, the relays E36 and ti alternately release their associated armatures. The segments or the coutator'll' are so arranged that with no wind blowing. one of the segments will be in contact with thebrush it or la.

I At ill I shows a wind vane having a shaft 82 and a commutator to which is-adapted to contact with one of tour it 4:51 at, 95, to, and ti, respectively, though lit-will be apparent from a turther understanding of my invention that any desired'nber may be provided. In the in stance shown, the brushes 9b and ti are connected rough aconductor at which leads toe relay ltd which is connected to the battery it througha conductor till, push button ti and condoctors .t'land tie relay iilil controls arma-= tures idl, ltd, and tilt, the armature tilt being movie into contact with a flexible contact member into. e flexible contact member into has connec thereto another flexible contact member illilb through which a circuit is normally made. when the relay ltd is energized a circuit is first made thro armature tilt and flexible contact delta, followed by a breaking of the circult W: ugh the flexible contact late. "The armatures Mill and ltd areanted to be moved into contact with stationary contacts the and told, respectively. x

b at or the wind vane at is connected through a conductor Ebb with a relay it'll which latter is connected through a conductor lot to the conductor till, and thence in a manner already described to the battery it. The relay Edi controls atures iii and'iili. The armature ii i is movable into contact with a flexible member lilo similar to contact iiltlcandwhich Y has connected thereto a flexible contact member.

itib to term a matte before break contact as previously described. earmature iii is adapted to be moved into contact with a stationary contact member lt'ic.

The brush it oi the wind vane ti, leads through a conductor lit to a relay lit which is connected to the conductor I08 and from thence to the battery or manner already described. The relay W5 controls armatures' ill and lit. The armature ill in rrrovable into contact with a flexible contact member iiBa having connected thereto a normally closed flexible contact member iitb to form a be before break contact. The armature tilt is adapted to be moved into contact with a stationary contact member title.

at lid and iti are shown conductors connected to a suitable lighting circuit such as 110 volt, 60 cycle alternating current. The conductor till is connected to the stationary contact. momhers lode, iltfld, idle, and. Mic. 'The conductor tilt is connected to a conductor I22 and a condoctor in leading respectively through the flood lights it and it. The conductor in lsconnected to the armatureri it directly and through a conductor I24 to the armature Ill. The conductor ill is connected directly to-th'e armature illt, and through a conductor M6 to the armature lit. Q

r t thus t w the y ltd is circuit is completed through both the flood lights iii and it through the conductors izhicontacts as ill and Ii, at airports, are lighted when an airplane is landing'or taking 0d so as to furnish general illumination of the landing field being traversed by the airplane, without producing a glare in the eyes of the aviator. Ordinarily flood lights are so located about an airport that. one or more may be lit so that the source of the beam is to the rear or to one side of the direction in which the airplane is landing or taking 0d; In-

asmuch as the number and location or flood lights depends upon the shape and conditions surrounding each particular airport, ll have'not shown, except conventionally, nor do I cl, any particular arrangement or order in which such flood lights are to be lighted. My invention isparticularly directed ,to a system of control whereby appropriatenood lights are -lighted autornatically in landing indications, responsive jointly to wind direction and wind velocity, which system oi control will now be descrlbed'iurther. I Y

The armatures 8%, till), Hi2, and flexible contact to are all connected to a common conductor ill. The armature did and the flexible contact iiltb are connected by means of a conductor ltd. When the relay it is energized, the armature the movesinto contact with alstationcry contact member til which is connected to a stationary contact member til, associated with the relay til, through a conductor itt, When the relay ill is energized, the armature tic moves into contact with the stationary contact member ill. The armature 63th, when the relay lit in lie-energized, is incontact with a stationary contact member it", while the armature bib, when the relay 8! is die-energized, is in contact with a stationary contact member 81". The contact members it and ti" are connected by means of a conductor iM which in'turn is connected to the conductor 9t leading to the wind vane ill. The armature tile, when the relay ht is one d, moves into contact with a stationary contact member 36" which is connected to a stationary contact member ti' by means of a conductor lot. The armatures btd and did, when the relays t6 and t'l are de-energized, are in contact with stationary contacts itil and Ni, both oil which are connected to a conductor Ml leading to the wind direction indicating apparatus to be described later.

The flexible contact member iii'lb and the ar-,

r Assuming now-that the master control circuit through the relay 83 has been caused to be closed by a sustained radiant energy signal, as previ-' ously described, and that a wind of suillcimt velocity is blowing to maintain both the relays do and ti energized, a circuit is i a as iollows:

accordance with direction for From battery 36 through conductor 48 to armature 02b and thence through stationary contact member 63" through conductor I44 and flexible contact I01b, through conductor I43 to flexible contact member II6b. From the flexible contact member II6b the circuit continues through conductor I3I to the armature I02 and flexible contact member I00b and from thence through conductor I32 to armature 814:: Both relays 86 and 81 being energized, the circuit continues from armature 81a to stationary contact 81' and thence through conductor I33 to stationary contact'86'. From the stationary contact 88' the circuit continues through armature "(1 through a conductor I6I to a brush I62 bearing against the wind vane shaft 82. vane in the position shown, the circuit continues through the shaft 82, the segment 83 and brush 84, through the conductor I06 to the relay I01 energizing said relay and continuing through conductor I08 to conductor IN and from thence back through push button 6| to and 31, to the battery 36.

When the relay I01 is energized, the armature III moves into contact with the flexible contact I01a before breaking the contact I61b. As soon as contact is made with the contact member I01a, a holding circuit for the relay I61 is established fromv the conductor I44 through the armature III and contact I 01a, the relay I01, conductor I08, and thence through conductor IM ,and back to battery 36 as previously described. Once the holding circuit, just described, is completed, a sudden change in wind direction does not affect a de-energization of the relay I01. When the relay I01 is energized, the armature II2 also comes in contact with the stationary contact member I01c, completing a circuit through flood light I0 as heretofore described.

Since it is possible to de-energize relay 63 only by pressing the push button 6|, and since a holding circuit has been established. for the relay I01, controlled from the master relay 63, the circuits Just described will remain completed and the flood light I0 will remain on until the push button 6i is pressed. When the push button 6| is pressed, the relay 63 is de-energized, breaking the circuit to relay'l01 through the'armature 63b and the circuit through the flood light J0 With the wind conductors 40 made through the relay I00, energizing it. a holding circuit is established through the armsture 63b and contact 83" through conductor I44, contact I01b, contact 612, conductor I3I, contact I00a, and relay I00 back through conductor IM to the battery 36 as previously described.

YVhen the relay I00 is energized, armatures I08 and I04 are pulled into contact with the stationary contact members I000 and 100d which closes the circuits through both flood lights I0 and II as heretofore described, lighting the fieldwill .now be described. Connected to the wind vane shaft and insulated therefrom by a sleeve I" is a commutator shaft l56 having a segmentalcommutator I61 secured thereto and adapted to selectively bear against brushes I66 to I6I inclusive, depending upon the direction of the wind. The four brushes are arranged at uniform distances around the commutator so as to allow an indication of four wind directions at 90 to each other though it will be apparent that any desired number may be provided.

Bearing against the commutator shaft I56 is a brush I62 which is connected to the conductor 84, which latter is also connected to the brush 88 bearing against the anemometer shaft 16. Leading from the brushes I58 to I6I, respectively, are conductors I63, I64, I66, and I61. The conductor I63 leads to a relay I88, the conductor I84 to a relay I68, the conductor I66 to a relay I10, and the conductor I61 to a relay I18. The relays I68, I10, and HI are connected in parallel to a conductor I12 leading to the armature 810. The relay I68 is connected in parallel with the relays 86 and 81 through conductor 68 which is connected to the battery,36 through conductors 46 and 48.

Controlled by the relay I" are armatures I14, 0

tures I18, I18, and I60 adapted to be brought into contact with similar stationary contact -members connected in parallel'when the relay is opened. The operation of the relays I00 and III is the same as that described for the relay I01, the circuits being completed through these relays when the wind vane'8l is in the proper position for the commutator 83 to contact with the brushes 85, 86, or 81, as the case may be. When the relay I00 is energized, a circuit is completed through both flood lights I0 and II. as already described, and when the relay H6 is energized, a circuit is completed through the flood light II only, as already described,

Should there be no wind blowing, or a wind 'of such low velocity that onlyone of the re-'.. lays 86 and 81 is energized, and assuming that to conductor I34 and conductor 88.

l rom conductor I34 the circuit goes through relay I00, energizing it and, thence back through conductor IN to push button 8I and conductors 48 and 81 tothe battery 36. Once the circuit is From I10 is energized. Controlled by the relay I69 are armatures 182, I88, and I84 which are brought into contact with associated stationary contact members connected inparallel when the relay I68 is energized. .similarly the relay I66 controls armatures I86, I81 and I88 which are brought into contact with associated stationary contact members when the relay I68 is energized. All of the stationary contact -members just mentioned are connected to a single conductor I13 leading to the conductor, I2I of the lighting circuit. a

Connected to the armature I14 is a conductor I8I which leads through wind direction indic'atingllght I8 to a conductor I 22 connected to the conductor H8. The armature I16 is connected to a conductor I82 leading through the wind direction indicating lights I6 and I1 to a conductor I83 which latter is connected through a conductor I84 to the conductor I22, and thence to the lighting circuit.' The armature I16 is connected to a conductor I86 which leads through the wind direction indicating light I2 to a conductor I84, and thence to the lighting circuit.

The armature I18 is connected to a conductor I81 which is connected to the conductor I96 leading through the wind direction indicating light I2 as Just described. Armature I18 is conaotasce nected to a conductor I 98 which leads through the wind direction indicating light I3 to the conductor I94 and also through wind direction indicating light I9 to the conductor I22 and the lighting circuit. The armature I80 is connected to a-conductor I99 which latter is connected to a conductor 2M leading through the wind direction indicating light I4 to the conductor Hit, and thence to the lighting circuit.

The armature I82 associated with the relay I69 is also connected to the conductor 2M and through the wind direction indicating light it. The armature N3 is connected to a conductor 202 which latter is connected to the conductor 1 492 leading through the wind direction indicating lights I5 and H to the lighting circuit. The

armature net is connected to a conductor 3W,

which latter is connected to a conductor 2% leading through the wind direction indicating light 20' to conductor I22 of the lighting circuits The armature I86 associated IE8 is also connected to the conductor 2M and Q the light 20 as just described. The armature ilt through a conductor 2% to the conductor to the lighting circuit.

IN is connected to a conductor 205 which latter is connected to the conductor IQt leading through the wind direction indicating lights l3 and It to the lighting circuit. The armature Hit is connected to a conductor 2t? which latter is connected to the conductor it! leading through the wind direction indicating light it Inasmuch as the wind direction indicating light It forms a part of every direction indication, it is connected directly across the lighting circuit from conductor its and remains lit at 'all times.

The operation of the wind direction indlcating lights is as follows: Assuming that there is a wind of sufficient velocity for the anemometer it to .hold both the relays lit and Bl energized and that the wind direction is that indicated by the wind vane ti with the coutator seg ment i511 bearing against the brush ltl lead-=' ing to the relay Ill, a circuit is made from bate tery it through conductor as to conductor id and thence through conductors he and he to stationary contact ilt'. From thence it continues through conductor H36, station r contact 81'' and conductor M2 to relay ill. From relay I ill the circuit continues through conductor it? to brush lti, segment ltl, shaft lit and brush let to conductor 8t and thence through conductor 31 to the other side of the battery 36. This energizes relay ill and brings the armatures lit, H5, and lit into contact bers. When this is done the lighting circuit is completed through wind direction indicating lights is, it, ill, and i2, in a manner already described. Inasmuch as the light [It is always on, there is thus outlined automatically a stand-= ard T indication of the wind direction.

The energization of the relays Hi8, I169, and till-is brought about similarly to that of relay llli the particular relay being energized depending entirely upon the wind direction and the brush with which the commutator segment ltl isin contact. Whichever relay is energized, a T is outlined through the completion of circuits through theproper direction indicating lights I2 to 20 inclusive to indicate to the pilot the proper direction for landing.

' Assuming now that there, is no wind blowing,

with the relay the relays 8t and 8! is energized, acircuit made through relay I69v which is connected directly to the negative side of the battery 36 through conductors 88, 48 and 49. Fromthe relay I89 the circuit proceeds back to battery 36 through the conductor I 42 to one of the armatures 8641 or did, depending upon which relay dd. or M is de-energized. The armatures 85d and 810'. are both connected to the conductor 8d so that the circuit'continues through conductors ,M and ill to the plus side of the battery 36.

which may be closed both in response to a radiant energy signal or in response to the manual closing of an associated circuit. It will be seen that once the master control circuit is closed, secondary circuits are selectively and automatically established under the control 'of-the wind velocity and. wind direction responsive means. The provision of automatic holding circuits for both the master control circuit and the secondary pended claims.

W 4-: ll claim is? l. In an airdrome lighting system, a plurality of sets oi lights arranged to indicate wind direction, a set of lights arranged to indicate safest direction for landing with wind below a predetermined minimum velocity, circuits for each set of lights, a separate relay controlling the circuits for each set, a circuit for energizing each 'relay, a wind vane and an anemometer, means operated by the wind vane and anemometer forcontrolling the energizing circuits of the relays, whereby a set of lights will be lighted to indicate the direction of the wind in the presence-oi a wind above a predetermined velocity, and the clrcuits insures that once the flood light are set selected set of lights will be lighted to indicate safest direction for landing in the absence of a wind of the said predetermined velocity.

2. In an airdrome lighting system, a plurality oi sets of lights arranged to indicate wind direc- 'tion, a set of lights arranged to. indicate safest direction for landing with wind below a predetermined minimum velocity, circuits for each set of lights, a separate controlling means for each of the circuits, 2. wind direction indicating means,

a wind velocity indicating means, and means operated by the wind direction and wind velocity indicating means for actuating the circuit controlling means, whereby a setof lights will be lighted to indicate the direction of the wind in the presence of a wind above a predetermined velocity and the selected set of lights will be lighted to indicate safest direction for landing in the absence of a wind of the said predetermined velocity. 3. In an airdrome lighting system, a plurality of sets of lights arranged to indicatewind direction, a set of lights arranged to indicate safest direction for landing with wind below a predetermined minimum velocity, circuits for each set of lights, a separate relay controlling the circuits for each set, a circuit for energizing each relay, a pair of relays of the slow to release type having normally closed control elements in series in the circuits for energizing the first mentioned relays, circuits for the pair of relays, a wind vane.

' means operated by the wind vane for selectively closing the circuits for energizing the relays controlling the wind direction indicating sets of lights, an anemometer, and means operated by the anemometer for successively opening and closing the circuits for the pair of relays responsive to wind velocity whereby a set oilig'hts will be lighted to indicatethe direction oi the wind in the presence 01' a wind above a predetermined velocity and the selected set of lights will be lighted to indicate safest direction for landing in the absence of a wind of the said predetermined velocity.

4. In an airdrome lighting system, a plurality of lights wired in sets to indicate win direction, a set of lights wired to indicate'saie t direction for landing with wind below apredetermlned minimum velocity, circuits for each set of lights,

a separate relay controlling the circuits for each set of lights, circuits for the relays, a wind vane, circuit closing means operated by the wind vane interposed in the relay circuits associated with the sets of lights indicating wind direction, an

anemometer, a pair of relays of the slow to release type associated with the anemometer, circuits for these. relays, means operated by the anemometer tor alternately opening and closing the latter circuits whereby both relays remain energized with the wind above a predetermined minimum velocity, and a plurality of circuits controlled by the last mentioned relays and interconnected with the circuits for the flrst mentioned group of relays, whereby a set of lights will belighted to indicate the direction of the wind in the presence of a wind above a predetermlned velocity and the selected set oi lights will be lighted to indicate sai'est' direction for landing in-the absence of a wind of the said predetermined velocity.

5. A lighting system for an airport having a' plurality of sets of lights arranged to indicate wind direction including a set of lights arranged,

' to indicate safest direction for land ng with wind relays controlling the wind direction indicatingsets of lights, an anemometer, means operated by the anemometer for opening and closing the circuits for the pair of relays of the slow to release type alternately with a frequency responsive to the wind velocity whereby the set-oi lights to indicate proper landing direction under prevailing 'wind' conditions is lit, selectively controllable circuits for the flood lights, relays controlling said circuits, and circuits for energizing the last mentioned relays interconnected with the other relay circuitsoi' the'sy stem, for selective joint controlby the anemometer and the wind 5 vane; 6..A lighting system for an airport having a plurality of sets of wind direction indicating lights and a plurality of flood lights, comprising selectively controllable circuits for the flood lights, a separate relay for controlling each flood light circuit, circuits for each set 01' the wind direction indicating lights, a separate relay for controlling the circuits for each set, a wind vane interposed in the circuits of the relays controlling the wind direction indicating lights, means operated by the wind vane for selectively closing said latter relay circuits, a plurality of relays of the slow to-release type having control elenients interposed in the circuits for the flood light relays and the wind direction indicating relays, circuits for said plurality of relays of .the slow to release type, an anemometer and means associated therewith for successively closing said last mentioned circuits responsive to wind velocity whereby a set of lights will be lighted to indicate the direction of the wind in the presence of a wind above a predetermined velocity and selected flood lights will be lighted.

1. A lighting system for an airport having a plurality of sets of wind direction indicating lights and a plurality of flood lights comprising selectively controllable circuits for the flood lights, a separate relay for controlling each flood light circuit, circuits for each set 01' the wind direction indicating lights, a separate relay for controlling the circuits for each set, a wind vane interposed in the circuits of the relays cont-rollin'g -the wind direction indicating lights, means operated by the wind vane for selectively 40 closing said relay circuits, a plurality of relays oi the slow to release type having control elements interposed in the circuits for the flood light relays and the wind directionindicating relays, circuits for said plurality 01' relays of the slow to release type, an anemometer and means associated therewith for successively closing said last mentioned circuits responsive'to wind velocity whereby aset of l ghts will be lighted to indicate the directionpf the wind in the presence of a wind above a predetermined velocity and selected flood lights will be lighted, and a master control means for all said relay circuits.

8.-A lighting, system for an airport having a plurality 01' sets of wind direction indicating lights and a plurality of flood lights comprising selectively controllable circuits for the flood lights, a separate relay for contro l n each flood light circuit, circuits for each set of the wind direction indicating-lights, a separate relay for controlling the circuits for each set, a wind vane interposed in the circuits of the relays controlling the wind'direction indicating lights, means operated by the wind vane for selectively closing said relay circuits, a plurality of relays oi the slow to release type having control elements interposed in the circuits for the flood light relays and the wind direction indicating relays, circuits for said plurality oi relays of the slow to release typ,-an anemometer and means associated therewith for successively closing said last mentioned circuits responsive to,wind velocity whereby a set of lights will be lighted to indicate the direction or the wind in the presence 18" trol means for all said relay circuits, and circult closing means associated with the relays controlling the flood light circuits for establishing a holding circuit through one of said relays when the master control circuit is closed and one of said relays energized.

9. YA lighting system for an airport having a plurality of flood lights and a set or lights indicating safest direction for landing with a wind blowing below apredetermined minimum velocity comprising selectively controllable circuits for the flood lights, a separate relay controlling minimum velocity.

each of the flood light circuits, circuits for the direction indicating lights, a separate relay controlling the circuits tor the direction indicating lights, a plurality or relays oi' the slow to release type with control elements interconnected with the circuits for the betorementioned relays, an

anemometer and means operated thereby tor successively energizing said last mentioned relays responsive to wind velocity, whereby selected flood lights and the set of lights indicating safest direction for landing are lighted in the presence of a wind below apredetermined GURDON H. WILLIAIWS. 

